Canon 55mm f1.2 s.s.c FD mount. This great lens just arrived from Korea. It set me back 300$ but living in Japan the shipping was only 16$ (^_^)
It came very securely packaged, was very well maintained and the focus ring is smooth.
This lens too should should be a good compliment to my Vivitar 70-210mm f2.8 FD that I also recently got my hands on from eBay. More on that lens here and my Canon 135mm f2 L lens EF lens that I found on Yahoo auctions. More on that bad boy here.
My everyday walk around lens will still be my E mount Zeiss 24mm f1.8 though ♥